1. Field of the Invention
The present invention relates to a process, and also an apparatus, for displaying three-dimensional video images.
2. Discussion of Prior Art
So-called sequential 3D-TV systems are known, for example from the International Patent Application WO 93/08665 of Applicant's assignee, Carl-Zeiss-Stiftung, which is incorporated herein by reference, and from U.S. Pat. No. 4,562,463. In these patent documents, the three-dimensional image to be displayed is simultaneously sensed by two respective video cameras from two perspectives, and the stereoscopic partial images obtained are stored intermediately in suitable memory units. After the intermediate storage has been completed, the stereoscopic partial images are displayed alternatingly on a suitable display. The viewer, in order to perceive a spatial impression, wears so-called shutter spectacles, which at any given time release the view of one of the two partial images and which are synchronized with the switching frequency of the stereoscopic partial images on the display. It is known, as an alternative to this, to place a screen shutter element having a large area directly in front of the display, while the viewer wears corresponding polarizing spectacles.
In the cited International Patent Application WO 93/08665, partial memories are provided for flicker-free display of the three-dimensional images. These partial memories can be read out as a partial image is read in. The synchronization cost for signal processing is thereby reduced in comparison with U.S. Pat. No. 4,562,463. The process disclosed in International Patent Application WO 93/08665 is fully satisfactory for three-dimensional display of images that contain little motion, such as, for example, in minimally invasive surgery. However, known disadvantages can result in the case of rapidly moving images or moving cameras. Thus, because of the selected reproduction sequence of the stereoscopic partial images, partial images that were taken earlier are displayed on the display at a later reproduction instant. A known "jittering" of the three-dimensionally perceived image can result for the observer.